In a microwave radio link, a local oscillator, generally of the transistor or diode type, generates radio-frequency signals of a predetermined power level and is usually frequency-stabilized by synchronization with a crystal-controlled reference oscillator. Conventional stabilization methods include phase coupling or automatic frequency control by means of a zero-frequency discriminator, as described in my prior U.S. Pat. No. 3,886,472. Such methods require the comparison of two waveforms of approximately the same frequency. Because radio links employ frequencies in the range of 2,000 to 13,000 MHz and because present crystal-controlled oscillators are capable of producing frequencies up to about 100 MHz, it is necessary to provide a chain of multiplication or division stages for stepping up the frequency of the stabilized oscillations or for stepping down the frequency of the microwave. Such chains are rather expensive and contribute to increasing the physical dimensions of the system. These disadvantages are aggravated by the fact that the various r-f bands require different multiplication or division factors; thus, several tens of separate chains of multiplier or divider stages are required for spanning the range of 1,800 to 8,500 MHz generally used for the various carriers in radio links. Furthermore, because division circuits have relatively narrow pass bands, it is often necessary to make more than one such circuit available for a given frequency band of 500 to 700 MHz, for example.